As the world struggles to adapt to the COVID-19 virus with the availability of effective vaccines, a Chinese study revealed disappointing news about the Sinopharm vaccine. It stated that the antibodies generated by receiving a third dose of the Chinese COVID-19 vaccine significantly decline after six months, and a fourth dose of the vaccine does not provide sufficient protection against the Omicron variant.
The study, published on the "medRxiv" website before peer review, indicated that using inactivated vaccines like Sinopharm as a fourth booster shot may not be optimal for enhancing antibody response against Omicron. The concept of inactivated vaccines typically involves disabling the virus's function by using heat or chemicals, which leads to the virus losing its ability to reproduce while remaining intact to allow the immune system to recognize it.
In the face of Omicron, researchers at a hospital affiliated with Sun Yat-sen University showed that the antibody effectiveness level against the disease dropped by 53% in combating Omicron within 26 weeks after the third dose of Sinopharm, compared to the levels recorded two weeks following the third dose. The study concluded that a fourth dose of the vaccine, administered six months after the third, does not significantly raise the antibody effectiveness level against Omicron.
Earlier, Chinese researchers from Shanghai Jiao Tong University and a laboratory in Shanghai specializing in infectious respiratory diseases stated in a study conducted last December that a booster produced by the Chinese company Sinopharm from its COVID-19 vaccine was much weaker in resisting the Omicron variant of the virus, although they added that the effectiveness of the vaccine against Omicron remains unclear.
